NEW YORK (AP) — Amazon says an incorrectly typed command during a routine debugging of its billing system caused the five-hour outage of some Amazon Web Services servers on Tuesday.

In a summary posted online, the Seattle company says a command meant to remove a small number of servers for one of its S3 subsystems was entered incorrectly and a larger set of servers was removed. A full restart was required, which took longer than expected due to how fast Amazon Web Services has grown over the past few years.

Amazon says it is making changes to its system to make sure incorrect commands won’t trigger an outage of its web services in the future.

Amazon is the world’s largest provider of cloud services, which entails hosting companies’ computing functions on remote servers.